Safety device for power-presses.



O. KNOTH.

SAFETY DEVICE FOR POWER PRESSES.

APPLICATION FILED APRJ, 1912.

1,065,051 Patented June 17, 1913.

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[ l lnl ilwf/n tav aom d max 6% G. KNOTH.

SAFETY DEVICE FOR POWER PRESSES.

APPLIOATION FILED APR. 1, 1912.

1,065,051 Patented June 17,1913.

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C. KNOTH.

SAFETY DEVICE FOR POWER PRESSES. APPLICATION TILED APR.1,'1912.

" 5 g5 1 Patented June 17, 1913.

4 SHBETS-SHBBT 3.

G. KNOTH.

SAFETY DEVICE FOR POWER PRESSES.

APPLIOATION FILED APR. 1, 1912.

1 0 5 051 a Patented June 17,1913.

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Specification of Letters Patent. 7

Application filed April 1, 1912. Serial No. 687,802.

' t; Y DEVICE FOR POWER-PBESSES'.

i v PatentedJune 17,1913.

To all whom it me .concem:

Be it known t at I, CONRAD Know, a

citizen of the United States, residing at 173 Jellifi' avenue, Newark, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Safety Devices for Power-Presses, fully described and represented in the following specification and the accompanying drawings, forming apart of the same.

This invention relates to that class of power-presses in which the driving-wheel is fore he hasremoved his hands from the dies,

with the result that his hands are caught between the dies and severely crushed or cutofi'.

The object of this invention is to avoid the use of a foot-treadle and to absolutely prevent the operator from reengaging the press-clutch until both his hands are removed from the dies in the press. This is eflected by providing a clutch-handle and a releasing-handle at the opposite sides of the press, both of which must be simultaneously moved by the operator in order to reengage the press-clutch. These two handles are so connected that neither is capable alone of re'ngaging the clutch, and a locking device is applied to the clutch-handle, and a cam is rotated by the press-shaft to throw the clutch-handle back to its normal position after each actuation, in which position it is locked until the releasing-clutch is again moved.

The invention will be understood by reference to the annexed drawing, in which- Figure 1 is a side elevation of a press containing the improvements, with the driving-wheel removed and the clutch-key shown in dotted lines, the parts being moved to permitthe automatic engagement of the pressclutch. Fig. 2 shows the press-shaft and the cam connections forrestorin the clutch handle to its normal position; ig. 3 is a front elevation of the press-frame and the safety appliances with the driving-wheel in section; Fig. 4 is a plan of the press; Fig. 5' is a section on line '5.5 in Fig. 6; Fig. 6 is a section on line 6-6 .inFig. 5', with the cam indicated by dotted lines; Fig. 7 is a section on line 7-7 in Fi 6; and Fig. 8 is a section on line 88 in Fig. 6. Figs. 7 and 8 show the parts at the right of their respective section lines.

The press is shown with a bed A having stanchions Bcarrying bearings G for the press-shaft D. A driving-wheel E'is shown fitted to turn loosely upon the shaft and its hub is provided with a clutch-bolt F adapted to engage a hole G. Its hub is provided wit-h an interior groove to engage one corner of a rocking-bolt b which is journaled in disks 6 keyed upon the shaft D' at opposite ends of the wheel-hub H. The rocking-bolt rocks in-the disks and is flattened to clear the bore of the hub when turned in its inoperative position by the contact of the finger b with a latch b.

The rocking-bolt is shown in its operative position. in Fig. 1 engaging the left hand side of the groove in the hub, and pressed into such position by a spring 5 on one of the disks, which holds the finger 72 in the path of the hinge-latch b, as shown in Fig. 3. The latch is operated by a clutch-handle K through suitable connections, including a rock-shaft m and link Z A spring m operating upon the bell-crank m holds the latch I) normally in the path of the finger D which rotates with the shaft d and the driving-wheel so long as the rocking-bolt is engaged with the hub, and is pressed backwardly by the latch b at each rotation so as to turn the rocking-bolt to clear the groove in the hub and disengage the driving-wheel from the press-shaft (Z. The finger b after turning the rocking-bolt clear of the hub still rests upon the tip of the latch 19 and remains stationary with the shaft D until the latch is withdrawn. The

tively restore the clutch-handle K toits normal position where it is automatically locked by the bolt 0.

1 Only a brief operation of the cam g is required to shift the clutch-handle K to the osition in which it is locked by the lock- Eolt c, and the cam is turned clear from the roll upon the slide 7' by the time that the rocking-bolt Z) is disengaged from the hub H; so that the latch b which is coupled to theslide 1" by the bell-crank can be freely moved without obstruction from the cam.

The press-shaft is in practice formed with a crank or'eccentric H shownin Fig. 3, and with a crosshead carrying a punch I to operate upon an object J in the die J upon the press-bed. The punch .I is shown in connection with the other grooves in Fig. 1, but the parts for reciprocating the punch are omitted, as they are common in such presses and form no part of the present invention. I I

The latch is so arranged as to arrest the rotation of the shaft when the punch I is raised, thus leavingroom above the die J for the operator to manipulate the object J upon the die. A shaft L is journaled in bearings upon a housing L at the right hand side of the bed and carries a clutchhandle K and a cam K. The shaft L is provided with a crank L connected to the latch b by rods Z and intermediate bellcrank m The cam is provided with a hole 0, and a lock-bolt c is sustained movably beneath the hole and pressed normally up ward into the hole by a spring 0. A rockshaft f is journaled upon the housing L shaft is turned by the releasing-handle. I

transverse to the cam-shaft L, and has a toothed coupler g fitted movably thereto upon a feather g. The rock-shaft is connected by cranks N, N and connecting-rod O With a releasing hand-crank P journaled upon the left hand side of the bed A, andeach movement of the releasing-handleo'scillates the rock-shaft. A spring 0 operates to hold the releasing'handle in its normal position shown by dotted lines P in Fig. 4. An arm h is fitted-loosely upon the rock-shaft j adjacent to the toothed coupler g, and is provided with notches h to engage the toothed coupler. A spring (Z presses the arm normally upward, and the arm is forked at the end, as shown in Fig. 6, to embrace the locking bolt 0, and is shaped to press upon a'shoulder d upon the lower part of the bolt, so as to depress the same in opposition to the spring d when the arm is engaged with the coupler and the rock- A spring 6 (see (Figs. 5 and 6) presses the coupler normally toward the arm it so as to engage the same at each oscillation of the rock-shaft; but means is provided to withdraw the cou'pler upon each actuation of the clutch-handle and cam-shaft, so that the movement.

locking-bolt 0 may automatically engage the hole cin the cam. This is effected by a tripper-arm Z pivoted u on thecasing L and having a forked en shown in Fig. 8, to embrace a groove m in thefcoupler, and a roller n projected past the edge of the cam K, as shown in Figs. 5 and 8. The cam has a raised face is which is adapted to crowd the roller 'n outwardly when the clutch-handle K is moved from its normal position shown in Fig. 3 (indicated by dotted lines If in Fig. 4), to the endof ts actuating movement, where it is shown in full lines in Fig. 4.

Theblutch-handle is indicated in its normal position by dotted lines k in Fig. 6, and in a partially'shifted position by dot- [ted lines 7: in the same figure, where the raised face upon the cam engages theroller n before the clutch-handle completes its The cam thus operates at each movement of the clutch-handle to disconnect the arm 7 from the coupler upon the'rockshaft, and this permits the locking-bolt '0 to automatically engage the cam when the clutch-handle is restored to its normal position, as shown in Fig. 8. The positive return of the clutch-handle to its normal po-, sition is not dependent upon the Wlll of the operator, but is effected by a cam 9 upon the press-shaft D, operating upon a slide 1' which is connected by a link 8 with the bell-crank m The bell-crank being connected to the cam-shaft L by the link P, the rotation of the cam g, at each reciprocating movement of the press-tools, pullsthe clutch-handle positively .back to its initial position. In this position it is automatically lockedby the bolt 0 and cannot again be moved by hand to start the press without first moving the releasing-handle P. It will thus be seen that the latch 5 cannot be retracted from its operative position in which it stops the press-shaft at each rotation, without first operatingthe releasing-handle 1 to retract the locking-bolt and then turn-' either hand is engaged with the press-tools. I

The spring 0 restores the releasing-handle P to its initial position after each movement so as to relieve the arm h from the pressure exerted by this handle, thus removing any obstruction to the automatic rising of the bolt 0.

This safety clutch device is adapted to power presses of all descriptions having a clutch with means for automatically throwing out the same at each stroke of the press, and the safety devices themselves may be varied in construction provided they inelude a clutch-handle for reengaging the press-clutch after it is automatically thrown out, a lock for the clutch-handle and means for disengaging the lock before the clutchhandle can be shifted. For instance, the locking-bolt is shown applied to the cam K, but it could be applied to the shaft L or to the rod Z and produce the .same effect.

The clutch-handle K and releasing-handle P are shdwn in the drawings arranged at the opposite sides of the bed to be within convenient reach of the right and left hands movement of the handle, an arm to disengage the bolt, a releasing-handle, ,and a coupler for connecting it detachably with the said arm.

2. In a power press, a safety device for actuating the press-clutch, comprising a cam-shaft, a clutch-handle and a cam thereon, a locking-bolt to prevent the movement of the handle, an arm to disengage the bolt, a releasing-handle, a coupler for connecting it det-achably with the said arm, and a tripping-arm actuated by the cam for shifting the coupler and operating to disconnect the releasing-handle from the locking-bolt at each actuation of the clutchhandle.

3. In a power press, a safety device for actuat-in the press-clutch, comprising a cam-sha t at one side of the press, a clutchhandle and a cam on said shaft with a bolthole in the said cam, a locking-bolt for automatically engaging the said hole, a rockshaft with arm fitted movably thereto to retract the locking-bolt, a releasing-handle at the opposite side of the press with connections to oscillate the rock-shaft, a, coupler movable with the rock-shaft-to engage the arm, and a tripping-arm connected with the coupler and actuated by the cam to disconnect the releasing-handle from the locking-bolt at each movement of the clutchhandle.

4. A safety clutch fora power press comprising a clutch and means for automatiits normal position for reengaging the clutch, a cam rotated once at each stroke of the press, the connections arranged and operated to throw the clutch-handle back to its normal position.

-5. A safety clutch for a power press comprising a clutch and means for automatically throwing out the same at each stroke of the press, a clutch-handle movable from its normal position for reengaging the clutch, a camrotated once at each stroke of the press, with connections arranged and operated to throw the clutch-handle back to its normal position, a locking-bolt operating automatically to secure the said handle in its normal position, and a releasinghandle for disengaging the locking-bolt.

6. A safety clutch for a power-press, comprising a clutch and means for automatidle when turned to its normal position, and

a releasing handle at the opposite side of the press with detachable connections to withdraw such locking-bolt.

7. A safety clutch for a power press comprising a clutch and means for automatically throwing out the same at each stroke of the press, a clutch-handle movable from its normal position for rengaging the clutch, a cam rotated once at each stroke of the press, with connections arranged and operated to throw the clutch-handle back to its normal osition, a locking-bolt operating automatically to secure the said handle in its normal position, a releasing-handle with a detachable coupler for connecting it to the locking-bolt, and means actuated by the clutch-handle in moving it from its normal osition, to disconnect the releasinghandle rom said locking-bolt.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

CONRAD KNOTH. Witnesses Gr. 0. SrUL'rs, M. E. J AHN. 

